CN114865300A - A dual-band ultra-wideband shark fin antenna - Google Patents

Abstract

The invention discloses a dual-frequency ultra-wideband shark fin antenna, comprising a metal floor, a dielectric substrate, a monopole and a non-enclosed ring oscillator. The dielectric substrate is placed vertically on the metal floor, the monopole and the non-enclosed ring oscillator are arranged on the same side of the dielectric substrate, and the monopole is arranged inside the non-enclosed ring oscillator; the monopole is composed of an upper rectangular structure , the middle rectangular structure, and the lower rectangular structure are connected in sequence; the non-closed ring oscillator is composed of the left ring structure, the upper ring structure, the right ring structure, and the lower ring structure in turn; the lower ring structure is connected with the lower rectangular structure. The feeds arranged on the metal floor are co-excited; the left ring structure is short-circuited with the metal floor. The invention can cover high and low frequency bands, the low frequency bandwidth can reach 56.9%, and the high frequency bandwidth can reach 87%.

Description

A dual-band ultra-wideband shark fin antenna

technical field

The invention relates to a dual-frequency ultra-wideband shark fin antenna, which belongs to the field of Internet of Things and microwave technology.

Background technique

In the traditional vehicle antenna design scheme, the GPS antenna and mobile communication antenna (2/3/4G mobile communication) are integrated in a small shark fin. However, with the use of 5G, V2X and other frequency bands, the integrated shark fin The number of antennas will become more and more, and the crowded space will cause electromagnetic interference problems such as low isolation and serious crosstalk, which will reduce the electromagnetic compatibility of the vehicle antenna system and affect its normal operation.

The multi-band broadband antenna can cover all possible working frequency bands with as few antenna units as possible, thus solving the problem that multiple antennas are difficult to coexist in a limited space.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention proposes a dual-band ultra-wideband shark fin antenna, which can cover both high and low frequency bands. The bandwidth at low frequency can reach 56.9%, and the bandwidth at high frequency can reach 87%, which can realize the use of multiple communication frequency bands including GPS, NB-IOT, LTE, 5G NR, and effectively solve the electromagnetic interference caused by multiple antennas. . It has the advantages of simple structure, excellent performance, easy fabrication and realization, etc., and has wide application prospects in the field of vehicle-mounted Internet of Things.

The present invention adopts the following technical solutions for solving the above-mentioned technical problems:

A dual-band ultra-wideband shark fin antenna, comprising a metal floor, a dielectric substrate, a monopole and a non-closed ring oscillator, wherein the dielectric substrate is placed vertically on the metal floor, the monopole and the non-closed ring The vibrator is arranged on the same side of the dielectric substrate, and the monopole is arranged inside the non-closed ring vibrator;

The monopole is formed by connecting an upper rectangular structure, a middle rectangular structure and a lower rectangular structure in sequence, wherein the upper rectangular structure and the middle rectangular structure are both perpendicular to the metal floor, the lower rectangular structure is parallel to the metal floor, and the upper rectangular structure is parallel to the metal floor. A rectangular structure is a rectangular structure with chamfered corners;

The non-closed ring vibrator consists of a left ring structure, an upper ring structure, a right ring structure, and a lower ring structure connected in sequence, wherein the left ring structure and the right ring structure are both perpendicular to the metal floor, and the upper ring structure and the lower ring structure are parallel to the metal floor;

The lower ring structure is connected with the lower rectangular structure, and is co-excited by a feed source arranged on the metal floor at the connection;

The left ring structure is short-circuited with the metal floor.

Further: the left ring structure and the upper ring structure can be divided into 3 sections according to any proportion, and the right ring structure can be divided into 2 sections according to any proportion, and the width of each section ranges from 0.004λ to 0.04λ. .

Further, the adjustment of the coverage frequency of the antenna can be realized by adjusting the ratio of the size of the cut angle on the monopole to the width of each segment on the non-enclosed ring oscillator.

Further: the angle range of the upper cut angle of the monopole is 0° to 60°.

Further: the dielectric constant of the dielectric substrate ranges from 1 to 100.

Further: the length of the metal floor ranges from 60mm to 100mm, and the width ranges from 4mm to 80mm.

Further: the position of the feed source can be freely moved left and right along the center line of the broad side of the metal floor.

Further: Lumped elements can be used to reduce antenna size.

Further, a reflector can be added to improve the radiation direction of the antenna.

Compared with the prior art, the present invention adopts the above technical scheme, and has the following technical effects: the present invention can cover both high and low frequencies, the bandwidth at low frequencies can reach 56.9%, and the bandwidth at high frequencies can reach 87%. In the limited space of the car shark fin, one antenna can be used to cover multiple communication frequency bands including GPS, NB-IOT, LTE, 5G NR, and reduce the electromagnetic interference caused by too many antennas in the shark fin in the past. It has the advantages of simple structure, excellent performance, easy fabrication and realization, etc., and has wide application prospects in the field of vehicle-mounted Internet of Things.

Description of drawings

1 is a schematic diagram of the front structure and reference coordinates of an antenna in an embodiment of the present invention;

2 is a three-dimensional schematic diagram and a schematic diagram of reference coordinates of an antenna in an embodiment of the present invention;

Fig. 3 is in the embodiment of the present invention, adopts the antenna reflection coefficient characteristic calculated by HFSS software;

Fig. 4 is the radiation pattern of the XY plane of the antenna calculated by HFSS software when the center frequency is 0.8 GHz in the embodiment of the present invention;

Fig. 5 is the radiation pattern of the XY plane of the antenna calculated by using HFSS software when the center frequency is 2.4 GHz in the embodiment of the present invention;

6 is an antenna gain calculated by HFSS software in an embodiment of the present invention;

In the figure, 1 is a monopole, 2 is a ring oscillator, 3 is a dielectric substrate, 4 is a metal floor, and 5 is a coaxial feed.

Detailed ways

Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, but not to be construed as a limitation of the present invention.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should also be understood that terms such as those defined in the general dictionary should be understood to have meanings consistent with their meanings in the context of the prior art and, unless defined as herein, are not to be taken in an idealized or overly formal sense. explain.

Below in conjunction with the accompanying drawings and specific embodiments, the technical solutions of the present invention are described in further detail:

As shown in FIGS. 1 and 2 , the structure of a dual-band ultra-wideband shark fin antenna of the present invention includes a metal floor 4 , a dielectric substrate 3 , a monopole 1 and a non-closed ring oscillator 2 , wherein the dielectric substrate 3 Vertically placed on the metal floor 4 , the monopole 1 and the non-enclosed ring oscillator 2 are arranged on the same side of the dielectric substrate 3 , and the monopole 1 is arranged inside the non-enclosed ring oscillator 2 .

The monopole 1 is composed of an upper rectangular structure 11 , a middle rectangular structure 12 and a lower rectangular structure 13 connected in sequence, wherein the upper rectangular structure 11 and the middle rectangular structure 12 are both perpendicular to the metal floor 4 , and the lower rectangular structure 13 Parallel to the metal floor 4, the upper rectangular structure 11 is a rectangular structure with cut corners.

The non-closed ring oscillator 2 is composed of a left ring structure 21 , an upper ring structure 22 , a right ring structure 23 and a lower ring structure 24 connected in sequence, wherein the left ring structure 21 and the right ring structure 23 are both perpendicular to the metal Floor 4, the upper ring structure 22 and the lower ring structure 24 are both parallel to the metal floor 4;

The lower ring structure 24 is connected with the lower rectangular structure 13 , and is jointly excited by the feed 5 disposed on the metal floor 4 at the connection. The left ring structure 21 is short-circuited to the metal floor 4 .

In the present invention, the monopole 1 and the non-closed ring oscillator 2 are connected together to form a radiation unit together. The cut angle α on the monopole 1 can be adjusted between 0° and 60°. The left ring structure 21 and the upper ring structure 22 on the non-closed ring oscillator 2 can be divided into 3 sections according to any proportion, and the right loop structure 23 can be divided into 2 sections according to any proportion, and the width of each section can be adjusted from 0.004λ to 0.04λ. The dielectric constant of the dielectric substrate 3 ranges from 1 to 100, and should be placed vertically on the center line of the wide side of the metal floor 4 . One end of the non-closed ring vibrator 2 is connected to the feed source, and the other end is short-circuited to the metal floor 4 .

The invention proposes a dual-frequency ultra-wideband antenna, wherein the radiating element of the antenna is composed of a ring oscillator and a monopole. It can use one antenna to cover multiple communication frequency bands including GPS, NB-IOT, LTE, 5G NR in the limited space of the car shark fin, and reduce the electromagnetic interference caused by too many antennas. It has the advantages of simple structure, excellent performance, easy fabrication and realization, etc., and has wide application prospects in the field of vehicle Internet of things.

In one embodiment, a FR4_epoxy material with a dielectric constant of 4.4 is used, and the size is 61mm*1mm*71mm; the size of the metal floor 4 is 80mm*60mm; The height of the source 5 is 6mm and the width is 2mm; the non-closed ring vibrator 2 is divided into four structures of left, upper, right and lower according to the clockwise. Proportional segmentation, the width of each segment is 2mm, 4mm, 2mm; the length of the upper ring structure 22 is 55mm, which is segmented from left to right according to the ratio of 2.2:5.1:2.7, and the width of each segment is 2mm, 1mm, 2mm; the right ring The structure 23 has a length of 61mm, and is segmented from top to bottom in a ratio of 6.7:3.3, and the width of each segment is 4mm and 2mm respectively; the lower ring structure 24 is 22mm in length and 2mm in width. In the monopole 1, the width of the middle rectangular structure 12 and the lower rectangular structure 13 are both 2 mm, the length of the lower rectangular structure 13 is 9 mm, the length of the middle rectangular structure 12 is 16 mm, and the upper rectangular structure 11 is a 29.5 mm*16.5 mm Cut off a triangle with a right-angled side length of 11mm and a cut angle α of 45° from the lower left corner of the rectangle.

Simulation calculation with HFSS software:

FIG. 3 is the reflection coefficient of the antenna calculated by the HFSS software in this embodiment, and the total available bandwidth of the two sections is 3.46 GHz. Among them, the low-band bandwidth covers 0.73-1.31GHz, the center frequency is 1.02GHz, and the relative bandwidth is 56.9%; the high-band bandwidth covers 1.87-4.75GHz, the center frequency is 3.31GHz, and the relative bandwidth is 87%. It can be seen that both frequency bands of the antenna are ultra-wideband.

FIG. 4 is the radiation pattern of the XY plane when the operating frequency of the antenna calculated by the HFSS software is 0.8 GHz in this embodiment. As can be seen from the figure, on the XY plane, the front-to-back ratio is only 3.6dB, showing good omnidirectionality in the low frequency band.

FIG. 5 is a radiation pattern of the XY plane when the operating frequency of the antenna is 2.4 GHz calculated by using the HFSS software in this embodiment. As can be seen from the figure, on the XY plane, the front-to-back ratio is 27.26dB, showing good directivity in the high frequency band.

FIG. 6 is the antenna gain calculated by the HFSS software in this embodiment. As can be seen from the figure, the average gain in the low frequency band (0.73—1.31GHz) is 6.1dBi (4.8—7.5dBi), and the average gain in the high frequency band (1.87—4.75GHz) is 1.1dBi (-1.38—3.0dBi). ).

To sum up, the present invention is a dual-band ultra-wideband shark fin antenna. In order to realize the ultra-wideband function, the radiation unit of the antenna is composed of a ring oscillator and a monopole. When the ring monopole composite structure is used, the antenna can cover both high and low frequency bands, and the bandwidth at low frequencies can reach 56.9% and the bandwidth at high frequencies can reach 87%. In the limited space of the car shark fin, it can cover multiple communication frequency bands including GPS, NB-IOT, LTE, 5G NR, and reduce the electromagnetic interference caused by too many antennas in the shark fin in the past. The antenna of the invention has a simple structure, is easy to produce and process, and has a wide application prospect in the field of vehicle Internet of Things.

The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited to this, any person familiar with the technology can understand the transformation or replacement that comes to mind within the technical scope disclosed by the present invention, All should be included within the scope of the present invention, therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (6)

1. A dual-frequency ultra-wideband shark fin antenna, characterized in that, comprising a metal floor (4), a dielectric substrate (3), a monopole (1) and a non-closed ring oscillator (2), wherein the dielectric substrate (3) be placed vertically on the metal floor (4), the monopole (1) and the non-closed ring oscillator (2) are arranged on the same side of the dielectric substrate (3), the monopole ( 1) be arranged inside the non-closed ring oscillator (2); The monopole (1) is formed by connecting an upper rectangular structure (11), a middle rectangular structure (12), and a lower rectangular structure (13) in sequence, wherein the upper rectangular structure (11) and the middle rectangular structure (12) are both connected. perpendicular to the metal floor (4), the lower rectangular structure (13) is parallel to the metal floor (4), and the upper rectangular structure (11) is a rectangular structure with cut corners; The non-closed ring oscillator (2) is formed by connecting a left ring structure (21), an upper ring structure (22), a right ring structure (23), and a lower ring structure (24) in sequence, wherein the left ring structure (21) ) and the right ring structure (23) are both perpendicular to the metal floor (4), and the upper ring structure (22) and the lower ring structure (24) are both parallel to the metal floor (4); The lower ring structure (24) is connected with the lower rectangular structure (13), and is jointly excited by the feed (5) arranged on the metal floor (4) at the connection; The left ring structure (21) is short-circuited to the metal floor (4). 2. dual-frequency ultra-wideband shark fin antenna according to claim 1, is characterized in that: described left ring structure (21), upper side ring structure (22) can be divided into 3 sections according to any proportion, and described right The ring structure (23) can be divided into two segments according to any ratio, and the width of each segment ranges from 0.004λ to 0.04λ. 3. The dual-frequency ultra-wideband shark fin antenna according to claim 2, characterized in that: by adjusting the size of the upper cut angle of the monopole (1) and the width of each segment on the non-enclosed ring oscillator (2) ratio to realize the adjustment of the antenna coverage frequency. 4. The dual-frequency ultra-wideband shark fin antenna according to claim 1, wherein the angle range of the upper cut angle of the monopole (1) is 0° to 60°. 5 . The dual-band ultra-wideband shark fin antenna according to claim 1 , wherein the dielectric constant of the dielectric substrate ( 3 ) ranges from 1 to 100. 6 . 6 . The dual-band ultra-wideband shark fin antenna according to claim 1 , wherein the length of the metal floor ( 4 ) ranges from 60 mm to 100 mm, and the width ranges from 4 mm to 80 mm. 7 .

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